This invention relates to a retractable and extendable awning and a control system for automatically extending and retracting the awning.
Retractable and extendable awnings are generally known from U.S. Pat. Nos. 1,075,385, 1,804,550, GB 1 175 723, GB 2 042 058, EP 0 084 076, EP 0 125 727, EP 0 489 186 and EP 0 795 660.
The present invention has as an object to eliminate inconveniences of the prior art by providing such an awning with improved features.
In accordance with this invention, a retractable and extendable awning, includes at least one arm support bracket, at least one arm having first and second pivoting arm sections, a front bar, a roller adapted to be mounted for rotation, a fabric cloth for winding about and unwinding from the roller, wherein the first arm section has a first end pivotally linked to the bearing support and a second end, the second arm section having a first end pivotally linked to the second end of the first arm section and a second end pivotally linked to the front bar.
According to another aspect of the invention, the front bar of the awning is provided with a weather sensor unit comprising a sensor which can detect movement of the front bar as a result of wind. Advantageously, the sensor unit is also provided with a light sensor, a rain sensor and a wind sensor. The additional wind sensor may be provided in addition to the movement sensor as this can only detect the presence of wind with the awning in an extended position. With the danger of wind removed it would be desirable if the awning can be extended automatically rather than manually. Hence the additional wind sensor which makes this possible. The movement sensor detects all vertical movements or shocks of the extended awning. If such movements occur outside of a predefined range a signal can be produced to effect retraction of the awning to prevent it from being damaged. The movement sensor can be based on the principle using a conductive fluid and two electrical contacts. If the fluid as a result of movement contacts both contacts an electrical connection is made. The number of electrical contacts within a given time frame can be used to detect movement. The viscosity of the conductive fluid determines the sensitivity of this type of movement sensor. Preferably the wind sensor is selected to be highly sensitive, whereas the movement or shock sensor can be of a much lower sensitivity. The wind sensor can be included in a wind catching body which is movably mounted with respect to the sensor unit. Such a wind catching body is preferably shaped to catch wind from all possible directions. Known wind detecting devices do only detect wind in a horizontal direction and are mostly mounted at a location remote from the awning which also does not help in recognising the actual danger level to which an individual awning may at times be exposed. Often gusts of wind blow vertically upward with respect to a facade of a building which carries the awning and this can be particularly dangerous if undetected. The present invention will cope with this situation more adequately. The sensor unit preferably communicates by means of wireless transmission with a control unit, which advantageously can be positioned indoor, and preferably the sensor unit is also programmed in a manner to save power. The sensor unit further comprises circuitry which at idle is in a sleep mode and consumes only 10 microamperes. An IRQ-pin is used to force a processor out of this sleep mode. This can be made to happen once for every 10 seconds or so. Upon awakening the unit will read the measurements of its sensors and compare these with threshold values stored in an internal table. Only when one of the values exceeds the specified threshold the unit will establish communication with either an indoor or outdoor control unit. Additionally the sensor unit will also establish communication with the control unit every one to five minutes, or so, to send a xe2x80x98livexe2x80x99 signal even without having to report a surpassing of a threshold value. The circuitry thereby enables the control unit to detect proper operation and communication of the sensor unit. During such predefined periodic communications the control unit can also transmit any new settings of threshold values to the sensor unit. Power supply for the sensor unit circuitry is provided by a rechargeable battery or accumulator which is charged by a solar cell. To economise on the investment for solar cells the solar cell is preferably composed of four individual cells. To allow charging of the battery with a relatively low voltage of 2 V, a step-up converter is used. This enables charging under even very low light levels, while under excessive light conditions the charging current will be limited to prevent damage to the battery.
According to yet another aspect of the invention an awning is, further provided with an indoor control unit. Upon installation particular settings for the outdoor weather sensor unit, such as sun and wind can be downloaded from the control unit to the sensor unit and stored at both ends in a programmable memory, such as an EEPROM, which memorises these settings. Only if the sensor unit detects a value outside of these settings it will establish communication with the control unit, so as to minimise transmissions between the two devices and the power consumption required thereby. If however the control unit does not receive the standard periodic xe2x80x9clivexe2x80x9d-signal transmission it will retract the awning and switch itself into manual mode. A suitable message may be displayed on a display device of the control unit to indicate this. The indoor control unit preferably is connected to mains supply and includes a transformer and a triac control for an electric motor incorporated in the awning or like sun protective device. Conveniently a high frequency circuit for wireless transmission of signals can be combined with the high voltage circuit board in the control unit. Another circuit board can be provided for the low voltage section of the control unit. The low voltage circuit board thereby contains the logical controls which can be fed by a low voltage, such as 5 V DC. These include a processor, a liquid crystal display, switches and optionally a temperature sensor. The processor comprises a control algorithm, a routine for decoding switch actuations and a display driver. To obtain an as adaptable as possible arrangement, the display driver and decoder for the switch matrix are included in a timer. An internal serial port is used for communication with a transceiver module. To control an electric motor for moving the awning from a retracted into an extended position and vice-versa a revolution counter and a power surge detection may be employed to detect the appropriate end positions of the awning. Such end position controls are usually incorporated in the electric motor units. An IRQ input and routine are however reserved in the control unit for the possible inclusion of an optional motor control in the control unit if so desired. It then also becomes possible to program the power surge (measured by a triac), which should result in the motor to cut out, with the help of the control unit. A main program algorithm has only a reduced number of tasks, which improves clarity and reliability. The main program thus includes two programming modes and decision sequences for intellectual control.
According to a still further aspect of the invention an awning is provided that further includes a hand-held remote control transmitter.
The invention also provides a control system in particular for an awning as referred to above, which includes at least one of a weather sensor, an indoor control unit and optionally a hand-held remote control transmitter, all preferably as referred to above.